How do military helicopters like the Blackhawk and CH-53, as well as the V-22 Osprey, perform mid-air refueling without their rotor blades (periodically and accidentally) contacting the drogue or fuel hose and causing a major accident?
I imagine that if the rotor blades did make contact with the fuel hose, either the fuel would be released and be sparked and ignite, or ingested by the helicopter turbines, or the rotor would break, or all of the above! When a helicopter is refueling, its rotor is nearly above the fuel hose, or at the maximum, maybe 20 feet away? It's easy to imagine a bit of turbulence or a few centimeters of cyclic movement (a sneeze perhaps?) is all that it would take for the rotor to dip and come forward and contact the hose.
For the Osprey the propellers / rotors are behind the nose of the aircraft and thus farther away from the fuel hose, but still, like a helicopter the Osprey's rotors are very large, and are exposed as opposed to the concealed compressor blades of a jet turbine.